Help please!! 😔😣😒

So my gf cheated on me this may and from then on out like I haven't been able to trust her because when she cheated she stayed away instead of comforting me she was out partying. And now tonight I called her 23 times and she didn't answer I'm done but I care so idk what should I do stay and try and work on it or just let it go? Help please!!!